Explosive compound



\VILLIAM It. QUINAN, SAN FRANCISCO, CALIFORNIA.

ExPLosavE COMPOUND.

SPECIFICATION forming part of Letters Patent No. 300,281, dated June 10, 188%.

Application filed April 27, 1883. (No specimens.)

To all whom it may concern;

Be it known that 1, WILLIAM R. QUINAN, a citizen of the United States, residing in the city of San Francisco, county of San Francisco, and State of California, have invented certain new and useful Improvements in Explosive Powders, of which the following is a full, clear, and exact description, which will enable others skilled in the art to which ihappertains to make and use the same.

My invention relates to that class of detonatin g explosives which more or less resemble gunpowder in their strength and mode of action, and are known as low powders, in contradistinction to the stronger gradesof detonating explosives.

The object of my invention is to make a low powder which can be readily exploded by the ordinary blasting cap by using a small proportion of nitro-glycerine in combination with other ingredients which form the essential elements of gunpowder.

It is a well-established principle that a very small percentage of nitro-glycerine will detonate or cause the sudden conversion into gas of gunpowder and analogous mixtures when the nitro-glyeerine itself is detonated by the fulminate-cap. I The difficulty to be overcome in making a low powder on this principle is to retain such small percentage of nitro-glycerine in sucha state that though distributed in the mixture it can be readily detonated \Vhen a small proportion of nitro-glyeerine is mixed with the pulverized ingredients of gunpowder or 'analogous gas-producing mixtures, it is so taken up and held that the ordinary blastingcap will not detonate it.

The substances ordinarily used in forming with nitro-glycerine the stronger or high-explosive powders may be classed as porous substances or absorbents proper and non-porous substances, or those which hold the nitro-glycerine by surface attraction. The power of this surface attraction for nitro-glycerine varics with difi'erent non-porous or non-absorb ent substances.

sion. Whatever power of surface attraction Some possess it slightly, and certain oily substances exercise a feeble repulbe taken up and held by a given weight of any such substance depends on the extent of surface exposed. A solid lump will hold only the amount which adheres to its surface. If, however, the lump be broken into fragments, new surfaces are formed, giving with every division an increasing surface of attraction. Owing to this attraction the particles of nitroglyeerine are separated more and more by being made to cover more surface until, if the process of division be carried far enough, the nitro-glycerine ceases to give any indication of its presence as a liquid and loses the property of detonation by the ordinary cap. greater the specific attraction of the substance for nitro-glycerine the more rapidly and readily will the extension of the surface brin about this condition of attenuation.

The nitrates of soda and potash and the various other explosive salts used as oxidizing agents in nitro-glycerine powders belong to this class of non-porous or non-absorbent substances which hold the nitro-glycerine by surface attraction. Their specific attraction for nitro-glycerine is comparatively strong.

Heretofore in forming high explosive powders with nitro-glycerine, these nitrates or other explosive salts have been. pulverized or reduced to fine particles. Owing to their great extent of surface in a given weight, these particles will take up and render practically inexplosive the small proportions of nitroglyeerine desirable to use in low powders. This result, being in all essential respects the same as that given by the employment of veritable absorbents or porous substances, has probably caused the value in the problem of making low powders of the distinction between 'the action of veritable porous absorbents and'such non-porous or surface-attracting substances to be hitherto overlooked. Thus, another inventor has found a means of counteracting this so-called absorption of the nit-ro-glycerine by coating or varnishing the pulverized salts used with some substance having less attraction than such salts for the nitro-glyoerine. I am the first to discover the causeof the failure to produce a low powder from the mixture of such explosive salts andsmall proportions of nitro-glycerine--viz., the great extent of 100 The ' surface attraction exercised by the salts in the pulverized condition, and the-remedy for this so-called absorption without changing the character of the surfaceviz., to lessen its extent by employing the salts in the form of larger masses or grains.

The carbonaceous ingredient or ingredients or the element which, in the explosion, furnishes the carbon or hydrogen,or both,to unite withthe oxygen of the nitrate or other explosive salt, may be one or several of a great variety of substances. For the purposes of my invention it should be essentially non-porous. To diminish as much as possible the surface, I generally employ a granular form, and by preference a spherical grain, as giving less surface than any other. As the nitrateor other explosive salt properly forms more than twot-hirds of the mixture,its condition is of greater importance than that of any other element. If its condition is such as to leave the nitroglycerine free when the two are mixed, it is easy to find a carbonaceous element sufficiently non-absorbent to be added in properly small proportion to the mixture without destroying the susceptibility of the nitro-glycerine to detonation by the cap. Almost any hard or dense form of carbon or hydrocarbon will fulfill this condition.

The'following is a typical. example of my invention: Unground nitrate of soda or cubic niter is taken in the crystallized commercial form and run through a sieve having twelve meshesto the linear inch. Of the crystals or grains which pass through the sieve, I mix sixty-seven parts, by weight, with fifteen and one-half parts rape-seed and five parts nitroglyc'erine. If the nitrate of soda has absorbed order in which the ingredients are mixed is immaterial, though it is more convenient to add the nitro-glycerine last. -After all the materials are in, thorough mixing can be obtained byv running them through a coarse s1eve.

For the nitrate-[of soda any other explosive salt .that can be used as anoxidizing' agent-- such as the nitrate of potash, of baryta, of

' lead, &c.- maybe substituted. 'The nitrate of ness and the greater regularity of its granu-. lation in the crystal form. If any part of it I should be pulverized by accidental attrition or otherwise, the dust should preferably be siftedout before it is passed through the sieve. For the rape-seed any other form or forms :ofnon-porous carbon or hydrocarbon maybe substitutedsuch as coal-screenings freedfrom dust .and run through a sieve, like the nitrate ofsoda, mustardseed, granulated resin, or

- xasphaltum, &c.' The purer forms of carbon and the carbonaceous element should be adj out passing it through the sieve.

moisture, it should be dried before using. The

soda is to be preferred, on account of its cheap 'justed by the chemical composition of the lat- .ter.

There should be enough oxygen furnished by the nitrate or explosive'salt to exidize the carbon to carbonic acid and the hydrogen to water. To make powders of various degrees of quickness and strength, the percentage of nitro-glyvcerine may vary from one to ten. In making the powdersit should be borne in mind that the nitro-glycerine should be so well distributed and securely held that there is no danger of leakage, and at the same time it should remain free enough to be readily detonated-that is, the powders should not be wet, neither should they be too dry, The

meshes of the sieve throughwhich the nitrate.

of soda or explosive salt is passed may vary in size from that given above, asgreater or less proportions of nitro-glycerine are designed to be employed. The finer the grains of itrate of soda the more nitro-glycerine they will take up. For larger proportions of nitroglycerine the finer sieves may therefore be used for the nitrate; or the carbonaceous ingredient may be wholly or partly pulverized. For smaller proportions of nitro -glycerine, coarser sieves may be used for the nitrate or explosive salt. The proper combinations of these alternatives will enable the powdermaker to produce a variety of low powders, each having its special application in blasting, and all of which are safe against leakage of the nitro-glycerine and susceptible to the action of the cap.

In making the powder, the unground crystallized nitrate may be used efficiently with- Regularity of granulation, though desirable, is not essential. I

For the purposes of this invention, the granulation of the nitrate or other explosive salt used, 'and'even of certain forms of carbon, may be effected by fusing each separately and running it through a sieve, or by other means.

For convenience, the crystallized form of the nitrate is to be preferred.

The essence of my invention consists in utilizing the principle of surface attraction.

\Vithout changing the character of the surface of the substances holding the nitro-glycerine, I lessen its extent by using the nitrate or explosive salt in masses large enough to leave the nitro-glycerine free to be readily detonated.

Among the advantages of my invention is this: The nitrate, being in the form of grains, is

less liable to injury by deli'qucscence. More over, the nitro-glycerine, having less surface to cover, acts more efficientlyas a coating impervious to moisture. To take full advantage of this, it is well to add the nitro-glycerineto the nitrate and mix it thoroughly before the other ingredients are put in. Its other advantages are its sensitiveness to the cap, cheapness, and thesmall amount in making it.

This application'is a division of my appliof labor required cation No. 43,786, on which. a Patent :No.' untriturated small masses, grains, or crystals; 260,786 was granted to me for one species .ofthe unpulverized ingredients remaining as the invention July 11, I882. separate grains in the mixture, substantially WhatI claim, :and desire to secure by :Letas described. 5 ters Patent, is- Dated San Francisco, California, April 20, 15

A low-explosivm powder composed of a 1883. small proportion of "nitrosglycerine, carbona- WILLIAM R QUINAN. -V ceous material," either pulverized or inthe Witnesses:

form of non-porous small masses or grains, JOHN A. WRIGHT,

IO and an explosive salt in the form of n0n-p0rous CHAS. D. WHEAT. 

